Valve for refrigerant compressors



' v j 91a w t "6 Aug. 28, 1951 T. G. CRIDER I 2,565,950

VALVE FOR REFRIGERANT COMPRESSORS Filed Aug. 5, 1946 I 4 Sheets-Sheet 1e INVENTOR. 5 7 70/7295 66/0518- 4 4a I Aug. 28, 1951 T. G. CRIDER2,565,950

VALVE FOR REFRIGERANT COMPRESSORS Filed Aug. 5, 1946 4 Sheets-Sheet 2INVENTOR. 7/70/295 6. 08 0/56.

HTEQYEXS.

Aug. 28, 1951 T. G. CRIDER 2,565,950

VALVE FOR REFRIGERANT COMPRESSORS Filed Aug. 5, 1946 4 Sheets-Sheet 5INVENTOR. 770M195 09/056.

A 1951 T. G. CRIDER 1 2,565,950

VALVE FOR REFRIGERANT COMPRESSORS Filed Aug. 5, 1946 4 Sheets-Sheet 4INVENTOR. 7770/7/95 Ce/ofe.

Patented Aug. 28, 195i i ooMl iiEssoits" i t Thomas G. Cr idei",.I;iina, Ohio; assignor t'b The Cridertfiorporatioii, Lima,-.Ohi','aeoorporaitibii' of Ohio Application August 1946, Serial No. 688,537 aClaims (01151-119) Thisinvention" relates to" a refrigerant? compressor' andlithas to do pai ticular ly with atom-" pressor ofa heavyduty type an'd es'pe'cially one for attaining: low temperatures" as' aresnowmtered' in deep freezers orother freezing appara tus.

While some" of thefeatures of the: invention may be employedincompressors other than-the: heavy duty type,- the: one; selected. for:purposes of: disclosure; .is' of: this type andzmoiie specifically 13 itis. a two-stage: compressor..- In: such compres sorsforpbtainingparticularly low temperatures;- there is awide difierential of pressuresencoun-x tered. which promotes: low: vvolumetric: efilcienoyi Tor meetthis situation; the compressor; of? the; present invention:is"ofthe:tw0'+stage: type in that there are two compression stages;This: splits; up: the wide overall: differentiala into "stages: and.

increases thevolum'etnic? efficiency of the CjQmy' pressor. By splittingthe compression func tion into stages, a' high efficiency 15 1 Obtained.In other words, for the same displacementrating a higher B.- t. u;rating is obtained with a reduc-- tion of powerinput. p n 7 Furtherobjects; of the invention include novel valving means: for promotin efilien operation, and silence'in operatingand structural features whichfacilitates-the manufacture of compresson unitsof this type; A stillfurther object-isthe provision of means which maybe termed;ap ump forforcibly furnishing lubricating. oil to; moving parts. This pumpinvolves; no moving parts in. andwf itself and accordingly canbecheaplymade and has an indefinitelife-period; p

Fig. 1 shows a cross sectionalview of a com-- pressor constructedin;accordance with the in--. vention and:illustrating,thaenclosing shell;some" of theoperating parts; and'the: lubricating sys-x tem.

bottom of Fig. lwithlthebottom plate-removed;

Fig. 3 is a diagrammatic-view showing; the re-i frigerating system ofthe 1 two stage variety.

Fig. 4 is an elevational view of one sideof a valve plate.

Fig; 5 is a view showingthe opposite side'ofthe Fig. 8 is an enlargedcross sectionallview taken substantially online 8-'-8i of Fig:- 7:showing the 551 Fig; 2 is a view lookinginto'the shell from' thefvalveine'mbers applied tliere to. Fig. 9' is? a diagrammatic-viewillustrating-the structure and'thefiinction of thepump. V a i Fig. 10 1sa cross 'setibnalview illustrating-the inlet structure of one of thecylinders.- A's shown'in Figi 1; the compressor em'bo'dies an-eXter-iorshell I with 'a bottom closure-' plate i and mount'ed 'on' the exteriorthereof are suitable supporting element's by means of which theshellmaybe-carried; Within the shell'i'dalbo'dii member preferably inthe-form of'a casting'li'av ing ia ring portion 5' tightly-'fitted-within 'the sheH I and W'h'iCh' is arranged tbre'ceive thestator" 5 of a driving" electric motor} For this purpb'sei a secondsupportin collar'olri r ing l may be en'i plO'ye'd; The exte or ofthe'sh'ell may be ar ranged to be cooled aind for this purpose radiatingtare applied'to' the eiiterio'r. V 'I ne bo'dy 'member-has a wallior'web portion-H1 which carries a bearihg 'sup porti l l whiehmay be"-lined with: suitable bear'ing 'material 12 in": which the sh'aft' l3 oft-he motor annature l4 is journalle'd as indicated." A thrust washer-isshown? at 15 to carry theivertioal load. Theiw'eb' 10' is rovidedwitn aertures 40 one= of'wh'ich may be eir'iploy'ed fonthe pa's'sage tliafe'through of conductors lt e'xten'ding 'to the' metor} and the conductorsmay passoutthrough the shell by means of plugs IT, as shown in Fig; 2?The" electricalconnections may be prot'ecte'd on" the'exteriorbyfiaprotecting cover I81 Mounted underneath the web I U andse'eiire'ii=- thereto are: a plurality of cylinders" arrangedabouttheaxis of-the driving shaft. As snewn in Fig; 2, there are three ofsuch cylindersfillus trated at Z I' an'dEZZ; e'alch'of which is provi'ded with a valve: pIate'ZB an'd a hea'd 2'4"h'eld thereto by caps'crewsas' indibated -by 'the out portion oncyliri'der 2 l; The body of eachcylinder is constructedindependently and are bolted twee underside ofthe body casting by bolts or cap screws Th p trite con'sti-uctiomfacilitates enlarging manufacturing tolerancess6 thatthe; cylinders maybe positio 7 ed 'a nd lined up properly-' fo'i the'reception of their'pistons. In'oth'i' word Referring now to Fig. 3, a two-stage system isshown. Following this system through with the flow of the refrigerant,the partially compressed refrigerant passes out from the compressorthrough conduit 30 and through a condenser 3| and back into thecompressor through conduit 32. The condenser 3| may be part of the wholecondenser employed. The fully compressed refrigerant passes out throughconduit 33 to a condenser or condenser portion 34 thence into a receivertank 35. The receiver tank 35 may or may not be employed as some systemsemploy a receiver tank and others do not, but the condensed refrigerantis then conducted through conduit 38 to an evaporator 38 and theexpanded gaseous refrigerant returns to the compressor through conduit31. a

The three cylinders are arranged to handle the refrigerant in thistwo-stage manner. Th gaseous refrigerant entering. the compressor entersfreely into the shell I as Fi 2 is viewed. This refrigerant passesupwardly through the web ill and particularly through the apertures 40provided therein (Fig. 2) with continued flow upwardly between thestator and the armature of the motor into the compartment 4| in the topof the shell. For two of the cylinders such as the cylinders 28 and 2|,the gaseous refrigerant now passes downwardly through passages 42 formedin the body casting. It will be understood that each cylinder 20 and 2|is provided with an inlet passage 42. For the moment, we shall merelyassume that the refrigerant passes through the cylinders and iscompressed thereby leaving the detailed description to follow and willcontinue with the path of the refrigerant through the conduits providedtherefor. The refrigerant gases entering the cylinders 20 through inlet42 is compressed thereby and in compressed form is discharged through aconduit 43. The refrigerant gases which enter the cylinder 2| in asimilar manner is compressed and discharged through a conduit 44. Thesetwo discharge conduits are coupled together as by means of a fitting 45and the conduit 38 passes through the shell I as at 48 and connects tothe fitting as shown. Thus, the cylinders 28 and 2| operate in parallelboth receiving refrigerant from within the shell and discharging thesame into the common line 38. This compressed refrigerant passes throughthe condenser section 3| and back into the shell through line 32 whichpasses into the shell at 41. This conduit 32 passes directly into thecylinder 22 and thus keeps the partially compressed refrigerant separatefrom the refrigerant gases within the shell. The line 32 connects intothe inlet of the cylinder 22 by a suitable fitting 48. This partiallycompressed refrigerant is now further acted upon and further compressedby cylinder 22 and it is discharged into a conduit 58 which passes outthrough the shell at and connects to line 33.

The pistons of the three cylinders are operated from a single crank 55on the motor shaft. There is a master connecting rod 56 mounted on thecrank for operating the piston in one cylinder as shown in Figs. 1 and 2and this master crank has a hub 51 formed with wings 58 to whichsecondary cranks are journalled. There is a secondary crank 59 for thepiston of each of the other cylinders connected to the hub 51 as at 88and, as illustrated in Fig. 1, connected to the piston in the cylinderby a wrist pin 8|. The piston in cylinder 28 is illustrated at 62 andsince all the pistons are the same only one need to be shown. It will beappreciated by those skilled in the art that rotation of the shaftreciprocates the pistons in their respective cylinders.

The refrigerant in gaseous form for cylinders 28 and 2| is drawn throughthe inlet passages 42. As shown in Fig. 1, the cylinder 28 has a passage85 which communicates with passage 42. The head 24 is formed with anintermediate partition to provide an inlet passage 55 and an outlet 61which communicates with an outlet passage 68 which connects to theoutlet line 43. The cylinder 2| is similarly constructed with its outletpassage to outlet conduit 44.

Between the .head and the body of each cylinder is a valve plate 18, asshown in Figs. 4 and 5. This plate is apertured at its corners for thepassage of the securing bolts. The plate has an aperture H which linesup with the inlet passages 65 and 66, as shown in Fig. 1; an inletpassage 12 leading into the cylinder from passage 66; an outlet passage13 leading from the cylinder to outlet passage 61 and a passage 14 whichlines up with the outlet passage 68 as shown in Fig. l. The top side ofthe plate is formed with a recess 15 in which is a rim-like seat 16extending around the outlet port 13 and a partial seat 11 through whichthe port 13 cuts. On the underside of the plate is a recess 88 in whichisa circular rib 8| providing a seat, a second supporting rib 82 whichis incomplete and intersects the inlet port 12, and an inner completering seat 83. It will be observed that the inlet port 12' iseccentrically disposed relative to the recess and the seats 8|, 82 and83. The surfaces of the ring-like seats are preferably all in the sameplane and in the plane of the face of the plate. Also, to be noted, theoutlet port 13 is eccentrically disposed in its recess.

The suction or inlet valve fits over the under side of the valve plateand it is in the form of a thin plate 88 accurately located by pins 81and having a port Ha to line up with the port H in the valve plate. Inits central portion the plate 86 is cut away to provide a flexiblesealing head 90 joined to the body of the valve plate by relativelynarrow flexi g portion 9| and the plate 86 has apertures 13a and 14a forlining up with the ports 73 and I4 of the valve plate. The head 98 seatson the seat 8|, the support 80 and the seat 83 and thus covers the port12.

The discharge valve is mounted on top of the valve plate 10. It has twospaced arms 93 secured to the valve plate by the pins 81 and the twospaced arms provide clearance for the port 12. It has an enlarged head94 which seats upon the rib 16 and support 1! and closes the dischargeport 13. It will be noted, with reference to Fig. 8,

how the head 94 seals against the complete circular seat'lB to close theport 13 while the partial ring 11 provides added support. The plate 86which is mounted underneath the valve plate 18 seats on the circularseat 8| to seal the port 12. The sealing portion 98 isv additionallysupported by the broken ring 82 while the inner small completesupporting rib 83 forms an oil trap chamber 98.. The valve plate andvalve structure for each of the three cylinders may, and preferably are,identical. However, the inlet for the cylinder 22, which is directlyconnected to the conduit 3|] at 48 is of a different construction thanthe inlet for'the' cylinders 28 and 2|. As shown in Fig. 10, thecylinder22 has an inlet passage a for direct connection with the fitting 48.Thus,

this cylinder does not have an inlet opening into the shell.

In the operation of each piston, the down stroke thereof draws the gasesin through the inlet port 65 or 65a. and 68 and. thence through the port12 in the valve plate. In this action, the valve head 90 flexes to openthe port as indicated by the dotted lines. On the up stroke of thepiston the valve head 90 closes the inlet port 12 and the compressedgases are discharged through the port 13'. In this action the valve head94 flexes away from the valve port 13 to open the same. Quietness ofoperation is promoted by this construction. The inlet port 12 is notcentrally positioned relative to the valving head 90 as will be clearlyseen by reference to Figs. 6 and 8. When this inlet valve opens, theaction can be likened to peeling the head 90 off of its seat around theport 72. In the closing action, some oil may be trapped in the recess 56thus further I facilitating silence in function. In a similar manner,the discharge valve is peeled from its seat 16 to open the port 73 butit is thought that no oil trap is needed for the discharge valve.

The pump construction is illustrated in Figs. 1' and 9. The motor shaftis bored to provide a passage I with one or more oil outlets I01 leadingto the bearing surface. The passage I00 extends through the crank throw55 with a passage leading to its bearing as indicated. Mounted on theend of the crank throw 55 is a tube I05 with an angularly disposed endI05. This tube may be concentric with the crank throw 55 and may be heldby a fitting I06 attached to the end of the crank throw.

This tube, therefore, operates or rotates about the axial center of thecrank shaft. As shown in Fig. 9, the center of rotation of the motorshaft is at a, while the center of the crank throw is at 1). ConsideringFig. 9, the direction of rotation is clockwise and the open end of thetube scoops up the oil in this movement. A pressure head is establishedwhich forces the oil up through the passage I00 for lubricatingpurposes. The open end of the tube is, of course, situated under thenormal oil level as indicated. Now, it will be appreciated that in suchrotation about the axis a, that centrifugal force is set up. The linesof centrifugal force are intended to be demonstrated in Fig. 9 by thelines 0, these lines radiating from the center of rotation a.Heretofore, pressure head tubes were required to overcome centrifugalforce and, therefore, since the centrifugal force increases with thesquare of the speed such devices were operative only below criticalspeeds since they would not function when centrifugal force overcomesthe pressure head. However, with the arrangement shown herein, it is notnecessary to overcome centrifugal force. In fact, the tube I05 may haveits open end so constructed and positioned that the centrifugal forcehas a component aiding the flow of oil into the open end of the tube.This is clearly indicated in Fig. 9. Thus, this pumping device can beoperated at any speed of rotation with the insurance that oil will bepumped into the conveying passages.

I claim:

1. A valve structure for a refrigerant compressor having a cylinder withan operating piston therein and a head for providing inlet and outletpassages from the cylinder, comprising a valve plate positionablebetween the cylinder and the head, said valve plate having an inlet portand having a recess surrounding the inlet port with the inlet portpositioned eccentrically thereof, a valve seat in the form of a ribpositioned in the recess and extending around the inlet port eccentrically, a flexible valve member assembled with the valve plate andarranged to seat on the rib to seal the inlet port, and. another rib inthe recess against which the valve member is adapted to seat, said ribproviding a chamber closed by the flexible valve member for the trappingof oil to cushion the action of the valve member in seating on the ribs.

2. A valve structure for a refrigerant compressor having a cylinder withan operating piston therein and a head for providing inlet and outletpassages from the cylinder, comprising a valve plate positionablebetween the cylinder and the head, said valve plate having an inlet portand having a recess surrounding the inlet port with the inlet portpositioned eccentrically thereof, a valve seat in the form of a ribpositioned in the recess and extending around the inlet porteccentrically, a flexible valve member assembled with the valve plateand arranged to seat on the rib to seal the inlet port, and another ribin the recess and substantially concentric thereof against which thevalve member is adapted to seat, said rib providing a chamber closed bythe flexible valve member for the trapping of oil to cushion the actionof the valve member in seating on the ribs.

3. A valve structure for a refrigerant compressor having a cylinder withan operating piston therein and a head for providing inlet and outletpassages from the cylinder, comprising a valve plate positionablebetween the cylinder and the head, said valve plate having an inlet portand having a recess surrounding the inlet port with the inlet portpositioned eccentrically thereof, a valve seat in the form of a ribpositioned in the recess and extending around the inlet porteccentrically, a flexible valve member assembled with the valve plateand arranged to seat on the rib to seal the inlet port, another partialrib within the recess which intersects the inlet port to provideadditional support for the valve member, a third rib within the partialrib positioned substantially concentric in the recess and providing anoil trapping chamber for cushioning the action of the valve member.

THOMAS G. CRIDER.

REFERENCES CITED The following references are of record in the file ofthis patent:

